On cement trucks or other materal handling systems, there is frequently used a chute of variable length which can be swung radially through approximately 180.degree. to receive cement at one end and carry it to a remote location such as a form or other conveyance. For instance on cement trucks the chute is mounted to rotate about the axis of a funnel receiving cement from the drum and is slanted downward to carry this cement to positions remote from the truck. When the chute is positioned radially to dispense the cement at a selected location, a brake is actuated to stop further rotation of the chute and hold it at that position.
In the past this brake has functioned to apply a braking force on the support for the hydraulic cylinder which raises and lowers the chute. The chute extends out from the truck as much as ten feet or more and can hold as much as two to three hundred pounds of cement. Thus when the chute is shifted radially while full of cement there is a substantial moment to be counteracted in stopping the chute. Naturally the swinging chute can cause damage if not closely controlled. This brake, because of its location, has been subject to failure and has been relatively ineffective in controlling chute positions. In the first place the position of the brake beneath the pipe has permitted cement and other materials to drop on the mechanism thereby frequently resulting in failure or ineffective operation. Additionally because the brake acts on such a small radius shoe, the braking moment in comparison to that resulting from the weight acting on the radius of the cement-filled chute has caused repeated failures. It is the purpose of the present invention to provide an improved braking system for a material dispensing apparatus such as the dispensing chute for a cement truck.